Furnace.



No. 882,616. PATENTED MAR. 24, 1908.

I H. BLUHM & J. H. REGAN.

FURNACE.

APPLICATION FILED MAY 20, 1907-.

i I J I I HENRY BLUHM AND JOSEPH H. REGAN, OF BOSTON, MASSACHUSETTS.

FURNACE Specification of. Letters Patent.

Patented March 24, 1908.

Application filed May 20, 1907. Serial No. 374,593.

To all whom it may concern: Be it known that we, HENRY BLUnM anc JOSEPH H. REGAN, citizens of the United States, and residents of Boston, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Furnaces, of which the following description, in connection with the accompanying drawing, is a specification, like letters on the drawing rcpresenting like'parts.

Our invention has for its object the improvement of that class of furnace shown in United States Patent No. 468;.124, dated February 9, 1892, and relates to a novel construction of the heating surfaces, and the combination therewith of a damper to control the direct and indirect draft.

Figure l in vertical section shows a sullicient portion of a furnace with our improvements added to enable our invention to be understood; Fig. 2 is a sectional detail in the line 00 relating particularly to the damper for controlling the direct and indirect draft.

Referring to the drawing, A represents part of the furnace jacket, the same having a top plate A, the jacket being provided with a series of pipes A any desired number, that lead hot air to the different apartments that the furnace is adapted to heat. The heating surfaces of the furnace comprise a circular exterior wall B, and a cone-shaped inner wall C, a cone-shaped portion B sustaining the outer wall B resting on the upper end of the fireot These devices are and maybe all su stantially as provided forin the furnace built under the patent referred to.

In accordance with our invention, instead of riveting together the upper ends of the walls B, C, we have closed the space between the upper ends of said walls by a cast metal ring E having a central down-turned flange 0 and e, 0 and to hold this metal ring gastight between the upper ends of said plates, we may place any usual luting between the flanges e, e and the upper ends of the plates B, C, and We unite the ring referred to to the walls B, O by adding to wall B a bracket 6 and to wall C a bracket 6, and these brackets are connected respectively by tie rods 6 c with the ears 6, e of the ring E.

The central heating drum D is provided at its top with a cap D having a flange d to fit the upper end of the drum D, the edges of the cap D being extended beyond the drum and provided with holes for the reception of tie rods (1 that enter like lugs (Z suitably united to the drum. The lower end of the drum is fitted to an upturned flangcf of a ring F provided with a series of lugs f, f said lugs being shown as provided with slots with which are engaged respectively the lower ends of tic-rodsfflj, the upper ends of said tie-rods engaging respectively lugs f connected with the drum, and lugs f con nccted with the inner wall 0, said tie rods sustaining said ring. The outer jacket of the furnace will be opened suitable for the reception of cold air, a portion of which will enter the pipe which leads through the space between the inner and outer wall, said pipe leading into the chamber between the inner wall and the drum so that the cold air has great opportunity to be heated in the space between the inner wall and the drum.

The outer wall B at a distance below its top is provided with a smoke pipe 0 that is led outwardly through the jacket A of the furnace, and has connected with it in usual or suitable manner the usual smoke pipe leading to the chimney. To provide for controlling the combustion of whatever fuel is deposited on the usual grate, not shown, in the fire-box B we provide a damper b having a handle Z)" extended outwardly through the jacket A. This damper comprises a central shaft with a circular plate connected therewith, and it coacts with a collar b shown best in Fig. 2, the collar having two stops 2, 3, one at each side the shaft 4 carrying the damper. The collar 6 is located at the lower end of a frame H comprising two baffle-plates ft, h, the bafflceplate it being the longer and. extending from the collar b upwardly to the flange e of the ring E, whereas the baffleplate h is shorter so that the products of combustion may readily pass over the top of said shorter baffle-plate when the damper is closed, as shown in full lines. The frame H constructed as described, insures, when the damper b is closed, that the products of combustion travel about the heating surface in the space between the walls B and C in the direction of the arrows, Fig. 2, and arriving at the shorter baffle-plate h, pass over the top thereof and enter the smoke pipe. When, however, the damper is open, as shown by dotted lines, the products of combustion thrown o'l'f fromithe consuming fuel may enter immediately the smoke pipe. After the fire is started the damper is closed. If desired, the smoke pipe outside the jacket A may have a damper and any cold air slide such as commonly used.

We have not herein shown the door through which fuel is fed into the furnace as the same may be as common to the patent referred to, or any other coal-burning furnace.

Having described our invention, what we claim as new and desire to secure by Letters Patent is 1. In a furnace, a heating surface comprising outer and inner walls, a central dome having a cap, a ring sustaining the lower end of said dome and fitting the lower end of said inner wall, said inner wall, ring and dome each having ears, and tie rods to connect said ring respectively with the ears of the dome and inner wall.

2. In a furnace, an outer and inner wall, each having ears, combined with a ring resting upon the upper ends of said walls, said ring having a flange depending between said walls, tie rods to connect said ring respectively with the ears of said outer and inner walls, a central dome having a cap, a ring sustaining the lower end of said dome and fitting the lower end of said inner Wall and tie rods connecting said last mentioned ring re-' spectively with said dome and inner wall.

3. In a furnace, a heating surface comprising an outer and inner wall, the outer wall having a smoke pipe, combined with a frame lnterposed between said walls, said frame having baffle-plates differing in height, and a damper in the bottom of said frame, said damper when closed insuring the passage of the products of combustion about said heating surface between said inner and outer walls and over the shorter baffle-plate into the smoke-pipe.

4. In a furnace, a heating surface comprismg outer and inner walls, a smoke pipe connected with said outer wall, a frame presenting baffle-plates of different height, and a damper at the lower end of said frame said damper when opened permitting the products of combustion to pass immediately from the grate into the smoke pipe.

In testimony whereof, we have signed our names to this specification, in the presence of two subscribing witnesses.

HENRY BLUHM. JOSEPH H. REGAN. Witnesses:

GEO. WV. GREGORY, MARGARET A. DUNN. 

